Multiple patterning is a class of technologies for manufacturing integrated circuits (ICs), which is developed for photolithography to enhance feature density (e.g., line density). The simplest case of multiple patterning is double patterning, where a conventional lithography process is enhanced to produce double the expected number of features. Double exposure is one of double patterning. Double exposure is a sequence of two separate exposures of the same photoresist layer. The double exposure technique allows manufacturability of minimum pitch features in a layout that may contain a variety of features. For example, the double exposure can be used to pattern parallel or adjacent trenches in the same layer. An approach for patterning trenches involves a sequence of two separate exposure and etching steps (2P2E) of independent patterns into the same layer, via litho-etch-litho-etch stages. When the sequence is completed, the pattern is a composite of the previously etched sub-patterns. By interleaving the sub-patterns, the pattern density can be increased, where the half-pitch is inversely proportional to the number of sub-patterns used. For example, a 100 nanometers (nm) trench or line pitch pattern can be generated theoretically from interleaving two 200 nm trench pitch patterns.